Types of printing and process
Lithography, also known as offset printing, is one of the most commonly used printing methods it is developed from early lithography and has since been improved to use metal zinc or aluminum as a plate, which is characterized by the printed part and non-printed part of the same plane, using the principle of oil and water repulsion, the image is printed on a rubber offset cylinder, and then the image is printed by the cylinder onto the paper. Offset presses have multiple printing devices that can transfer different colors. Lithographic printing has accurate color registration, easy plate making, low cost, soft tones, and rich layers.
Letterpress printing was first invented and is one of the oldest printing techniques, characterized by coloring the image and text of the raised portion of the layout and printing it directly on paper. It is applied like a stamp, with the raised area inked and printed directly on the substrate. This printing method cannot print multi-layered, colorful prints, and its expressiveness is greatly restricted, while it has advantages for printing large areas of monochrome prints.
Gravure printing is a rapidly developing printing method, its principle is the opposite of letterpress printing, the printed part is concave in the layout, and the non-printed part is smooth. The concave part is used to fill the ink, and the ink on the surface of the printing plate is scraped clean before printing, and after putting on the paper and applying pressure, the recessed part of the print pattern is transferred to the paper.
Hole plate printing is also called screen printing, that is, a printing method using a screen as the plate. The specific method is to create a graphic and plate film on the printing plate in two parts, the role of the plating film is to prevent the passage of ink, while the graphic part of the ink leakage through the external scraping pressure to the substrate, thus forming the printed graphics. The principle is to dig and cut holes in the flat plate, then apply ink so that the ink leaks through the holes onto the substrate.
Hole plate printing can be printed on a wide range of substrates, from large advertisements to business cards, and can be printed on paper, cotton, silk, plastic, glass, wood, metal, and other materials. For example, the printing of fonts on our common cars, the printing of graphics on external packaging boxes, etc., especially in the printing of bottles or packaging containers has advantages.
Digital printing is a very comprehensive technology, covering a number of technical areas such as printing electronics, computers, and network communications. The so-called digital printing, that is, the electronic file from the computer directly to the printing machine, eliminating the steps of color separation, plate, plate making, trial, etc., for a small print run (less than 1,000 copies) of four-color printing operations is very effective, from input to output, the entire process can be controlled by one person, to achieve a starting print.